MANAGEMENT CONSIDERATIONS

SPECIES: Abies bracteata
WOOD PRODUCTS VALUE :
Bristlecone fir has no commercial timber value; populations are too
small and inaccessible. It does not, however, appear to have any
legal protection from cutting.
IMPORTANCE TO LIVESTOCK AND WILDLIFE : PALATABILITY :
NO-ENTRY
NUTRITIONAL VALUE :
NO-ENTRY
COVER VALUE :
NO-ENTRY
VALUE FOR REHABILITATION OF DISTURBED SITES :
NO-ENTRY
OTHER USES AND VALUES :
NO-ENTRY
OTHER MANAGEMENT CONSIDERATIONS :
Bristlecone fir is rare but found in sufficient numbers and distributed
widely enough that potential for extinction is low at this time [25].
The Pacific Southwest Station of the United States Forest Service is
researching bristlecone fir genetics and population viability [32].

BOTANICAL AND ECOLOGICAL CHARACTERISTICS

SPECIES: Abies bracteata
GENERAL BOTANICAL CHARACTERISTICS :
Bristlecone fir is a native, evergreen, medium-sized tree. Mature
height ranges from 30 to 100 feet (9-30 m) [21]. Average heights at 100
years of age were reported as 40, 70, and 90 feet (12, 21, and 27 m) for
summit, transition, and ravine sites, respectively [27]. Bristlecone
fir is easily distinguished by a dense branching pattern that begins
near the ground and terminates in a tall, narrow point [6,21]. Branches
tend to decline or droop [21]. Mature ovulate cones are 3 to 4 inches
(7.6-10.1 cm) long and have long, needle-like points (0.78 to 1.57
inches [2-4 cm]) on the ends of the scale bracts, giving the cone a
frilled or bristled appearance [1,6]. The needles are flat, stiff, and
1 to 2 inches (2.5-5 cm) long [21,22]. The bark of mature stems is
smooth to slightly fissured and broken into appressed scales [21].
RAUNKIAER LIFE FORM :
Phanerophyte
REGENERATION PROCESSES :
Large crops of bristlecone fir cones are produced every 3 to 5 years
[6,33]. Seeds are parasitized by seed chalcids (wasps). Up to 100
percent of the total bristlecone fir seed crop is parasitized some
years, but occasional large cone crops exceed the parasitization
capacity of the chalcids. A large cone crop in 1971 resulted in viable
seed production in 1973 [27]. The winged seeds are chiefly dispersed by
wind [33]. In a greenhouse study, 80 percent of viable bristlecone fir
seeds germinated under a 5 degrees Fahrenheit (3 deg C) diurnal
temperature range. Above 73.4 degrees Fahrenheit (23 deg C), however,
germination rates decline. After-ripening, cool, and/or moist
treatments are not required for germination [27].
Bristlecone fir seedlings are sensitive to drought. Repeated
desiccation and high surface temperatures were probably reponsible for
the 1974 absence of bristlecone fir seed germination on chaparral,
grassland, and summit sites despite the good cone crop of the previous
fall. During that time, drought resulted in mortality of first year
seedlings on all sites except very near the coast and on new (created
after 1970) burns [27].
SITE CHARACTERISTICS :
Bristlecone fir occurs in windswept canyons on steep, rocky, or gravelly
sites at elevations ranging from 690 to 5,164 feet (210-1,571 m). The
average slope of bristlecone fir sites ranges from 35 to 40 degrees;
adjacent forests have an average slope of 25 degrees [27]. Average
annual precipitation is between 35 and 40 inches (998-1,000 mm) at
around 4,000 feet (1,216 m) in the Santa Lucia Mountains [25,27]. Less
than 2 percent of annual precipitation falls between June 1 and
September 30 [27]. The confinement of bristlecone fir to the Santa
Lucia Mountains and its absence from the Sierra Nevada are consistent
with the species' apparent requirement for a mild climate and low summer
evaporation rates [1].
Bristlecone fir occurs on soils derived from ultrabasic rocks but is not
limited to them [24].
SUCCESSIONAL STATUS :
Facultative Seral Species
Bristlecone fir height growth is correlated with the amount of light
striking the forest floor. Summer light levels below 30 langleys per
day are limiting to sapling growth [27]. Bristlecone fir groves are
probably climax on steep slopes. Bristlecone fir is a member of canyon
live oak communities, which are climax woodlands on steep slopes in the
Santa Lucia Mountains. Fire in canyon live oak woodlands can cause
internal shifts in species composition, but the area occupied by the
plant community usually does not change. Repeated burning may convert
open canyon live oak stands to chaparral, but the community will again
succeed to canyon live oak with long fire-free intervals [7].
SEASONAL DEVELOPMENT :
Staminate cones shed pollen in May. Ovulate cones mature in late
August of the same year, shedding bracts and seeds in September [6].

FIRE ECOLOGY

SPECIES: Abies bracteata
FIRE ECOLOGY OR ADAPTATIONS :
Bristlecone fir is concentrated on steep, rocky, fire-resistant sites
[13]. Bristlecone fir occurs on sites that have experienced fire less
frequently than the surrounding forests [27]. The presettlement fire
history of the Santa Lucia Mountains is not well known. Data for fires
during the Native American (11,000 years BP-1792 A.D.) and the
Spanish-Mexican (1792-1848) periods are scarce. The Anglo period
(1848-1929) included much indiscriminate burning by prospectors,
hunters, and ranchers. By the late 1800's, tales of huge fires in the
Santa Lucia Mountains were common in newspapers and government reports
[12]. A probable mean fire interval for lightning fires alone was
estimated for oak woodlands (in which bristlecone fir can occur) as 10
to 30 years. The mean fire interval for mixed evergreen forests (in
which bristlecone fir occurs) was estimated at 30 to 100 years for
lightning fires. Recent fire history (since 1929) gives a mean fire
interval of 215 years for mixed evergreen forests [9]. Talley and
Griffin [29] reported a range of 19 to 78 years between fire scars (from
1640 to 1977) on sugar pine in the area where bristlecone fir occurs.
Because of topography, the fire-free interval for bristlecone fir stands
on steep slopes is probably longer than any of these figures.
POSTFIRE REGENERATION STRATEGY :
Tree without adventitious-bud root crown

FIRE EFFECTS

SPECIES: Abies bracteata
IMMEDIATE FIRE EFFECT ON PLANT :
Bristlecone fir is easily killed by fire due to its dense branching
habit and thin bark [1,12].
DISCUSSION AND QUALIFICATION OF FIRE EFFECT :
NO-ENTRY
PLANT RESPONSE TO FIRE :
Frequent or intense fire probably eliminates bristlecone fir [12]. An
August, 1977 wildfire burned 178,000 acres in the Santa Lucia Mountains.
The fire was extremely intense due to a large accumulation of dead brush
and other fuels. Many bristlecone fir groves escaped the fire because
they occurred on steep, rocky terrain that did not carry the fire. The
largest bristlecone fir in the area (51 inches [129.5 cm] in diameter)
appeared undamaged 10 months after the fire. Ground fires did not burn
into many of the fir stands, though trees on the edges of the stands
were killed [12]. Griffin [12] suspected, however, that insect damage
would eventually kill more trees than the fire. He based this
supposition on the work of Talley [27], who observed that two
bristlecone fir groves lost only a small number of trees as a direct
effect of the 1970 Buckeye Fire, but had higher mortality rates as a
result of postfire insect damage.
DISCUSSION AND QUALIFICATION OF PLANT RESPONSE :
NO-ENTRY
FIRE MANAGEMENT CONSIDERATIONS :
NO-ENTRY